Adipogenesis can be spatially and temporally regulated by extracellular matrix (ECM). We hypothesized that the regulation of hyaluronic acid (HA), a component of the ECM, can affect adipogenesis in ...fat cells. The effects of HA on adipogenesis were investigated in vitro in 3T3-L1 cells and in vivo in high-fat diet-feeding C57BL/6J mice.
We investigated the effects of HA by degradation of pre-existing or synthesized HA and artificial inhibition of HA synthesis in adipogenesis.
In vitro adipogenesis in 3T3-L1 cells was inhibited by treating them with exogenous hyaluronidase (HYAL) and with 4-methylumbelliferone, which inhibited the synthesis of HA in a concentration-dependent manner. In vivo, abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice was suppressed by exogenous HYAL 10(4) IU injections, which was associated with reduction of lipid accumulation in liver and increase of insulin sensitivity.
Changes in the ECM such as accumulation of high molecular weight of HA by HAS and degradation of HA by endogenous HYAL were essential for adipogenesis both in vitro and in vivo.
Abstract
We present the star cluster catalogues for 17 dwarf and irregular galaxies in the HST Treasury Program ‘Legacy ExtraGalactic UV Survey’ (LEGUS). Cluster identification and photometry in this ...sub-sample are similar to that of the entire LEGUS sample, but special methods were developed to provide robust catalogues with accurate fluxes due to low cluster statistics. The colours and ages are largely consistent for two widely used aperture corrections, but a significant fraction of the clusters are more compact than the average training cluster. However, the ensemble luminosity, mass, and age distributions are consistent suggesting that the systematics between the two methods are less than the random errors. When compared with the clusters from previous dwarf galaxy samples, we find that the LEGUS catalogues are more complete and provide more accurate total fluxes. Combining all clusters into a composite dwarf galaxy, we find that the luminosity and mass functions can be described by a power law with the canonical index of −2 independent of age and global SFR binning. The age distribution declines as a power law, with an index of ≈− 0.80 ± 0.15, independent of cluster mass and global SFR binning. This decline of clusters is dominated by cluster disruption since the combined star formation histories and integrated-light SFRs are both approximately constant over the last few hundred Myr. Finally, we find little evidence for an upper-mass cut-off (<2σ) in the composite cluster mass function, and can rule out a truncation mass below ≈104.5M⊙ but cannot rule out the existence of a truncation at higher masses.
We propose a method (GREML-LDMS) to estimate heritability for human complex traits in unrelated individuals using whole-genome sequencing data. We demonstrate using simulations based on whole-genome ...sequencing data that ∼97% and ∼68% of variation at common and rare variants, respectively, can be captured by imputation. Using the GREML-LDMS method, we estimate from 44,126 unrelated individuals that all ∼17 million imputed variants explain 56% (standard error (s.e.) = 2.3%) of variance for height and 27% (s.e. = 2.5%) of variance for body mass index (BMI), and we find evidence that height- and BMI-associated variants have been under natural selection. Considering the imperfect tagging of imputation and potential overestimation of heritability from previous family-based studies, heritability is likely to be 60-70% for height and 30-40% for BMI. Therefore, the missing heritability is small for both traits. For further discovery of genes associated with complex traits, a study design with SNP arrays followed by imputation is more cost-effective than whole-genome sequencing at current prices.
The proven candidate genes for amelogenesis imperfecta (AI) are AMELX, ENAM, MMP20, KLK4, FAM83H, and WDR72. We performed mutation analyses on seven families with hypomaturation AI. A novel WDR72 ...dinucleotide deletion mutation (g.57,426_57,427delAT; c.1467_ 1468delAT; p.V491fsX497) was identified in both alleles of probands from Mexico and Turkey. Haplotype analyses showed that the mutations arose independently in the two families. The disease perfectly segregated with the genotype. Only persons with both copies of the mutant allele were affected. Their hypomineralized enamel suffered attrition and orange-brown staining following eruption. Expression of WDR72 fused to green fluorescent protein showed a cytoplasmic localization exclusively and was absent from the nucleus. We conclude that WDR72 is a cytoplasmic protein that is critical for dental enamel formation.
Speleothem CaCO
δ
O is a commonly employed paleomonsoon proxy. However, inferring local rainfall amount from speleothem δ
O can be complicated due to changing source water δ
O, temperature effects, ...and rainout over the moisture transport path. These complications are addressed using δ
O of planktonic foraminiferal CaCO
, offshore from the Yangtze River Valley (YRV). The advantage is that the effects of global seawater δ
O and local temperature changes can be quantitatively removed, yielding a record of local seawater δ
O, a proxy that responds primarily to dilution by local precipitation and runoff. Whereas YRV speleothem δ
O is dominated by precession-band (23 ky) cyclicity, local seawater δ
O is dominated by eccentricity (100 ky) and obliquity (41 ky) cycles, with almost no precession-scale variance. These results, consistent with records outside the YRV, suggest that East Asian monsoon rainfall is more sensitive to greenhouse gas and high-latitude ice sheet forcing than to direct insolation forcing.
Abstract
The Legacy ExtraGalactic UV Survey (LEGUS) is a multiwavelength Cycle 21 Treasury program on the
Hubble Space Telescope
. It studied 50 nearby star-forming galaxies in 5 bands from the ...near-UV to the I-band, combining new Wide Field Camera 3 observations with archival Advanced Camera for Surveys data. LEGUS was designed to investigate how star formation occurs and develops on both small and large scales, and how it relates to the galactic environments. In this paper we present the photometric catalogs for all the apparently single stars identified in the 50 LEGUS galaxies. Photometric catalogs and mosaicked images for all filters are available for download. We present optical and near-UV color–magnitude diagrams for all the galaxies. For each galaxy we derived the distance from the tip of the red giant branch. We then used the NUV color–magnitude diagrams to identify stars more massive than 14
M
⊙
, and compared their number with the number of massive stars expected from the
GALEX
FUV luminosity. Our analysis shows that the fraction of massive stars forming in star clusters and stellar associations is about constant with the star formation rate. This lack of a relation suggests that the timescale for evaporation of unbound structures is comparable or longer than 10 Myr. At low star formation rates this translates to an excess of mass in clustered environments as compared to model predictions of cluster evolution, suggesting that a significant fraction of stars form in unbound systems.
Summary
The study aims to evaluate the rate of transition to osteoporosis in 360 RA patients and estimate the rescreening intervals of bone mineral density (BMD) testing. Osteoporosis was newly ...developed in 24.8 % during mean follow-up of 7.4 years. The estimated time of a BMD testing interval was dependent on the baseline T-score in RA patients.
Introduction
Although BMD testing is routinely performed in RA patients, the interval between BMD tests has not been determined.
Methods
We retrospectively recruited 360 consecutive female patients with RA, who underwent repeated BMD testing, with a mean age of 53.7 ± 10.2 years and a mean follow-up duration of 7.4 ± 5.0 years. We stratified the study participants into five groups based on their baseline T-score range. The testing interval was defined as the estimated time for 10 % of patients in each subgroup to transition to osteoporosis. Competing-risk analyses were performed with sensitivity analysis by menopausal status and risk factors for transition to osteoporosis.
Results
At baseline, 15 % of screened patients had osteoporosis, and during follow-up, that proportion increased to 24.8 %. The estimated BMD testing interval for 10 % of patients to develop osteoporosis was 9.6 years for those with normal BMD, 7.6 years for those with mild osteopenia, 4.7 years for those with moderate osteopenia, and 2.1 years for those with severe osteopenia. No significant risk factor for transition to osteoporosis was identified in this cohort.
Conclusions
Our data indicate that osteoporosis will develop in less than 10 % of female RA patients during rescreening intervals of approximately 9 years for those with normal bone density at baseline, 7 years for those with mild osteopenia, 4 years for those with moderate osteopenia, and 2 years for those with severe osteopenia at baseline. BMD interval in RA patients could be adjusted according to their baseline BMD T-scores.
This study aimed to elucidate the role played by Enterobacter asburiae KE17 in the growth and metabolism of soybeans during copper (100 μm Cu) and zinc (100 μm Zn) toxicity. When compared to ...controls, plants grown under Cu and Zn stress exhibited significantly lower growth rates, but inoculation with E. asburiae KE17 increased growth rates of stressed plants. The concentrations of plant hormones (abscisic acid and salicylic acid) and rates of lipid peroxidation were higher in plants under heavy metal stress, while total chlorophyll, carotenoid content and total polyphenol concentration were lower. While the bacterial treatment reduced the abscisic acid and salicylic acid content and lipid peroxidation rate of Cu-stressed plants, it also increased the concentration of photosynthetic pigments and total polyphenol. Moreover, the heavy metals induced increased accumulation of free amino acids such as aspartic acid, threonine, serine, glycine, alanine, leucine, isoleucine, tyrosine, proline and gamma-aminobutyric acid, while E. asburiae KE17 significantly reduced concentrations of free amino acids in metal-affected plants. Co-treatment with E. asburiae KE17 regulated nutrient uptake by enhancing nitrogen content and inhibiting Cu and Zn accumulation in soybean plants. The results of this study suggest that E. asburiae KE17 mitigates the effects of Cu and Zn stress by reprogramming plant metabolic processes.
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